1. Field of the Invention
The present invention relates to an electric compass, preferably an electrical field detector, and more particularly refers to a detector that is applied as much as in the field of science, industry, as well as in minor, educational and/or domestic experiments, wherein the compass detects electric fields indicating the presence of an electrical field by orienting or aiming a needle in a way similar to a compass for locating and detecting magnetic fields and/or poles.
2. Description of the Prior Art
Up to the present there is no knowledge of the existence of instruments of simple and accurate operation to detect electrical fields. It is only known that, in the electrical and magnetic field, metal detectors are used for the localization of, inlay and/or underground metallic pipes.
Devices for measuring electric current intensity flowing through a conductor, such as the amperometric pliers, are also known. These devices detect magnetic fields generated by said electric current around the conductor, and the equivalent value in the amperes corresponding scale, may be read.
As it is well known, in the proximity of a body electrically charged, attraction forces appears in the presence of electric charges of the opposite sign, which repulsion forces appear for charges having the same sign that the one of the body. The space where the repulsion or attraction forces are generated, is defined as the electric field. Formally it has been established that the direction of the electric field is the one that extends from the positive charges towards the negative charges. If the charges that take place under this electric field are in equilibrium or in balance, said electric field is denominated the electric static field, the features of which, like in the case of moving charges, can be measured in magnitude, sense and direction. The magnitude of the electric field measured in a special point of the region where this field has been generated is defined as electrical potential, which potential not only depends on the amount of accumulated charges by the body, but also by the geometry and distribution of the charges in said body.
Thus, for example, taking two isolated spheres having the same amount of electrostatic charge with equal sign, either positive or negative, with sphere "A" being bigger than sphere "B", the electrical potential individually measured from a distance "d" in a point P, will be larger in the case of the small sphere "B". This is because the repulsion forces between charges of same signs cause said charges to be homogeneously distributed on the entire sphere surface. Therefore, the density of the charges distributed in the surface of these spheres, and observed in each case at equal distance from point "P", is greater than the density of charge on sphere A.
In accordance to the foregoing, in the bodies of irregular surface, the density of charges is less in flat zones than in curved zones and the greater amounts of charges by surface unit is found in the end or vertex of the parts that defines acute angles, this effect being known as point effect, where, consequently, the electrostatic potential is larger.
It is also to be mentioned that the electric charge accumulation takes place as much as in electrically conducting materials as it is in isolating or dielectric material. In solid conductor bodies, because of its crystalline structure, the atoms can be ionized by losing one or more electrons, which electrons are defined as free electrons by the moving capacity thereof through the conductor and the direction of an electric force. However, there are no free electrons in the dielectric materials, so there are no charges capable of moving through materials. However, the atoms, and in a general way the molecules of any dielectric material, show a structure that can be defined as elastic because its balance is subject to deformations provoked by the action of electrical, or even mechanical efforts. Thus, it can be said that by the consequence of said deformation, the atoms or molecules can be polarized, and have, in this way, a positive pole and a negative pole. These features of the material, particularly the dielectric features may be used as a principle of the operation of an electrical field detector.
3. Summary of the Invention
It is therefore an object of the present invention to provide an electric field detector, capable of detecting any electric field magnitude and providing a quick visualization of the direction of the electric field.
It is even another object of the present invention to provide an electric field detector, preferably a manually operated detector, that can be taken into practice in a simple and economical way, and that has a simple construction and is made of common and low cost materials.
It is a further object of the present invention to provide an electric field detector comprising a non electrical conducting detector needle, having a rotation center rotatably mounted in a needle-supporting stand having a supporting pin, the pin and the needle being disposed in a box made of a non electrical conducting material, at least one portion of box defining an observation window to see said needle from outside the box.
The above and another objects, features and advantages of these invention would be better understood when taken in connection with the accompanying drawings and description.